Eric Dumazet 3b24d854cb tcp/dccp: do not touch listener sk_refcnt under synflood ...

When a SYNFLOOD targets a non SO_REUSEPORT listener, multiple
cpus contend on sk->sk_refcnt and sk->sk_wmem_alloc changes.

By letting listeners use SOCK_RCU_FREE infrastructure,
we can relax TCP_LISTEN lookup rules and avoid touching sk_refcnt

Note that we still use SLAB_DESTROY_BY_RCU rules for other sockets,
only listeners are impacted by this change.

Peak performance under SYNFLOOD is increased by ~33% :

On my test machine, I could process 3.2 Mpps instead of 2.4 Mpps

Most consuming functions are now skb_set_owner_w() and sock_wfree()
contending on sk->sk_wmem_alloc when cooking SYNACK and freeing them.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2016-04-04 22:11:20 -04:00

..

ccids

dccp: re-enable debug macro

2014-02-16 23:45:00 -05:00

ackvec.c

dccp: drop null test before destroy functions

2015-09-15 16:49:43 -07:00

ackvec.h

net: dccp: Remove extern from function prototypes

2013-10-19 19:12:11 -04:00

ccid.c

dccp: drop null test before destroy functions

2015-09-15 16:49:43 -07:00

ccid.h

net: dccp: Remove extern from function prototypes

2013-10-19 19:12:11 -04:00

dccp.h

tcp/dccp: fix hashdance race for passive sessions

2015-10-23 05:42:21 -07:00

diag.c

sock_diag: specify info_size per inet protocol

2015-06-15 19:49:22 -07:00

feat.c

dccp: kerneldoc warning fixes

2014-11-18 15:26:31 -05:00

feat.h

net: dccp: Remove extern from function prototypes

2013-10-19 19:12:11 -04:00

input.c

dccp: spelling s/reseting/resetting

2014-11-18 15:26:32 -05:00

ipv4.c

tcp/dccp: do not touch listener sk_refcnt under synflood

2016-04-04 22:11:20 -04:00

ipv6.c

tcp/dccp: do not touch listener sk_refcnt under synflood

2016-04-04 22:11:20 -04:00

ipv6.h

inet: includes a sock_common in request_sock

2013-10-10 00:08:07 -04:00

Kconfig

net/dccp: remove depends on CONFIG_EXPERIMENTAL

2013-01-11 11:39:34 -08:00

Makefile

dccp: Policy-based packet dequeueing infrastructure

2010-12-07 13:47:12 +01:00

minisocks.c

tcp/dccp: fix hashdance race for passive sessions

2015-10-23 05:42:21 -07:00

options.c

dccp: remove obsolete code

2014-01-04 20:18:49 -05:00

output.c

net: Generalise wq_has_sleeper helper

2015-11-30 14:47:33 -05:00

probe.c

Use 64-bit timekeeping

2015-11-01 17:01:16 -05:00

proto.c

net: rename SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA

2015-12-01 15:45:05 -05:00

qpolicy.c

dccp qpolicy: Parameter checking of cmsg qpolicy parameters

2010-12-07 13:47:12 +01:00

sysctl.c

dccp: make the request_retries minimum is 1

2014-05-14 15:34:16 -04:00

timer.c

inet: get rid of central tcp/dccp listener timer

2015-03-20 12:40:25 -04:00